Get your pretty little ribbons, two pieces if you aren't sure how long just wrap about four times on your wrist because its going to be folded up :D

Alright now you have your ribbons at the length you want them, you can use the same color, i had pink and white, set them up like this, the left side is going to be the beginning

Sorry my flash is annoying!
but make a knot where the ends aren't separate. from the last picture basically the left side

Here is the knot, now separate your ribbons. make sure you have two straight ones, you can tape them down and also the loop so its easier. we are going to be working with the two white ribbons for now.

If you look at the white we have sort of a backwards number "4". The ribbon on the right is going to come forward though.

As i said before the ribbon on the right comes in front of the other ribbon, then it goes under the two pink ribbons and back on top of the left white ribbon.
HOPE THIS MAKES SENSE :D

this is where you realize that if you taped down the pink ribbon life was easier.
Just pull tight on the two white ribbons so you get this triangle looking knot

now take the left ribbon put it OVER the pink this time

take the right ribbon and go over the left UNDER the pink and back over the other ribbon.

repeat steps 5-9 until it looks like this remember to pull tight so you have enough ribbon and are able to see the knots.

So maybe you guys were wondering how i got the pink in the middle, well here it is!
When you are a tiny bit before the middle you can change the color, simple put the white ribbons under and bring the pink ones out.

do steps 5-9 with the pink ribbon until you are happy with the length of it

you can see here how you have that color change.

So if you go back to white just do what you did to go to pink. finally tie the longer strands that you may have at the end so your hard work doesn't undo itself.

you can cut the ribbon if its still too long, i just tied a knot at the end and put it through the loop twice.